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#### Things to Watch for and Some Helpful Tips and Suggestions

ChorusNT and PC-DMIS are different measuring systems, and some intrinsic characteristics need to be carefully considered. The following list contains some tips and suggestions:

Automatic Measuring Cycle

The DMIS Standard states that in a MODE/AUTO section the features are measured with the automatic cycle, ignoring any eventually present PTMEAS.

Since ChorusNT supplies automatic cycle for POINT, CIRCLE, SPHERE and SLOT (CPARLN), all these cases are translated into the corresponding AUTO feature. However, due to the intrinsic differences between Chorus and PC-DMIS, you should carefully verify their execution.

In SLOT (round slot) automatic cycle, ChorusNT takes first two points on one of the straight sides. PC-DMIS however, takes the points on the rounded ends of the slot.

STAR TIP Probes

PC-DMIS recognizes the ChorusNT SNSDEF extension that defines a star probe. Be careful that the PC-DMIS setup for the Probe Head orientation corresponds to ChorusNT SNSMNT specification.

CW43, CW43L, and IW42 Wrist Mounting conventions

ChorusNT and PC-DMIS conventions for the roll angle are different. While PC-DMIS can correctly adjust it during the import of a Chorus DMIS routine, to be safe, be careful the first time you execute the imported routine.

Theoretical values in FEAT statements

PC-DMIS always uses both Theo and Actual values, which should be correct (not too much off a deviation from actual values). If the deviation is great, you may have problems, especially with features used in alignments. This is because PC-DMIS defines two matrices for each alignment:

- First, the CADTOPART matrix. Based on the theoretical values, this convert THEO values in features.

- Second, the MACHINETOPART matrix. Based on actual measured values, this converts actual measured values in features.

Since ChorusNT doesn't have the CADTOPART matrix, it always uses the actual measured values. If you have the wrong nominal values, you only become aware of them if you execute an OUTPUT statement on that feature. To verify correctness, you should add them into the original DMIS routine OUTPUT statements for your features, especially for the alignment features.

FILNAM

FILNAM in ChorusNT specifies the name of the output file when using the DISPLY/STOR command. PC-DMIS recognizes it but this command must appear after the DISPLY in the DMIS routine. Consult your DMIS manual for more information.

VFORM

The ChorusNT vendor format statement is V(label)=VFORM/ALL. It translates into a PC-DMIS FORMAT/TEXT command that has the following information:

- MEASURED

- NOMINAL

- DEVIATION

- UP_TOL

- LO_TOL

- CRIT/OOT

The final PC-DMIS FORMAT command will look like this:

FORMAT/TEXT,OPTIONS,ID,HEADINGS,SYMBOLS,SD;MEAS,NOM,DEV,TOL,OUTTOL, ,

DEFGRF

DEFGRF statement is a Chorus extension that lets you define dialog boxes with buttons and input fields. PC-DMIS imports this command and creates a script using the BASIC language (Cypress Enable). Due to different screen resolutions, it’s possible that the resulting dialog box may need some adjustment. You can modify the Basic Script file using PC-DMIS's Basic Script Editor.

FROM and GOHOME

ChorusNT's conventions move the head center not the tip's ball center. While the PC-DMIS import can make the necessary offsets, you should use a low feed the first time you execute the imported ChorusNT routine inside PC-DMIS.

MRRPCS

In ChorusNT this command defines the reference system to be used in a routine created with ChorusNT's MIRROR Utility. PC-DMIS does not support the import of Chorus mirrored routine. You should instead use PC-DMIS's more powerful and complete mirror utility on a .prg file created by importing the "left side" Chorus routine.

GAUGE

In ChorusNT this statement defines and measures a sphere gauge, specifying the name: G(label), the diameter, and the stem direction. It also optionally specifies the center position, the incidence angle, and the number of points used to measure it.

GAUGE/SPHERE,G(label), diam, i, j, k, [angle, x, y, z, npoints]

Because of the different parameters, PC-DMIS translates this into two commands. The AUTO/SPHERE and the CALIBRATE ACTIVE:

F(label)= AUTO/SPHERE

The AUTO/SPHERE command uses the same name, diameter, and direction as the GAUGE statement. If the center position was not specified and during execution you manually select the first point on the top of the pole, then init=1 and perm=1, otherwise init=0 and perm=0.

PC-DMIS can also adjust the orientation, angle_vec, and normal_vec values accordingly.

CALIBRATE ACTIVE TIP WITH FEAT_ID=F(label), QUALTOOL_ID=label, MOVED=YES

CALIB

In ChorusNT this statement calibrates the specified probe using the specified sphere gauge G(label)

CALIB/SENS, S(probe),G(label), [angle]

PC-DMIS translates this statement into these three commands:

TIP/ T1A..B..

The tip command will have the same AB angles as the S(probe) ) statement.

F(label) =AUTO/SPHERE

CALIBRATE ACTIVE TIP WITH FEAT_ID=F(label), QUALTOOL_ID=label, MOVED=NO